Dolphins are as smart as 3-year olds, and dogs as smart as two-year old children, and some chimps are better at remembering things than any adult I know. But what do intelligence comparisons actually show us?
On the surface, human babies appear to be miles behind the rest of the animal kingdom. After all, foals can get up and gallop in the first minute of life. Whale calves can instantly swim with their pod. But human babies can’t do much at the start of life.
One reason human infants are so behind the curve is that our gigantic brains have to make it out of our moms’ pelvises (which aren’t terribly large because we walk on two legs). In order for a baby human to come out with the brain development of a baby chimp, we’d have to gestate for 18-21 months, writes zoologist Adolf Portmann.
When it comes to comparing dogs and babies, Stanley Coren, a biologist at the University of British Columbia, has crunched the numbers for years. He estimates that dogs have a similar intelligence to a 2.5-year old child. That benchmark comes from a couple of different tests.
First off, Coren looked at verbal comprehension for babies and dogs. He found that the average dog can understand about 165 words, including signs and signals – about the equivalent of a 2-year old baby. Canine high-achievers, on the other hand, can understand about 250 words — equivalent to a 2.5-year old baby.
Coren points out that dogs never pass the mirror test – they’re not able to comprehend a reflection in the mirror. Human babies start to pass this test around 18 months, though Coren says the average is 3 years.
When it comes to social understanding, dogs are even more advanced – equivalent to a human adolescent. Dogs are very savvy about “who’s moving up or down the social ladder, and who is sleeping with whom,” Coren told KinderLab.
Not everyone agrees that gauging infants and animals is a helpful thing to do. Alexandra Horowitz, a psychologist at Barnard College, says that the comparison both overstates and understates dogs – and babies. “The dog is very good at doing dog-things, and the child is developing a talent for doing human-things,” Horowitz told KinderLab.
“When, around 2, my son become highly verbal, it’s true that the divergence between the dog and child increases. But my dogs still knew things that my son did not. And my dogs may still be better readers of my intent, in some arenas, than my son is. Apart from which, they know a lot about smell,” Horowitz says.
But what if a universal intelligence test could even the playing field for animals, humans and machines? Two computer scientists, José Hernández-Orallo of the Polytechnic University of Valencia, in Spain, and David Dowe of Monash University, in Australia, are working on a test that wouldn’t rely on language and could assess intelligence in groups of animals (like a swarm of ants working collectively). The issue, says Dowe, is that the interface has to work for all types of creatures and machines.
Coren says he hopes that people do treat dogs differently when they read about their mental abilities. “You begin to find all these parallels” when discovering how best to work with babies and dogs, he says. “The same kind of advice that people learn about kids will work with dogs, if you treat a dog like a toddler.”